Persistent and worsening racial and ethnic disparities in maternal and infant outcomes in the US are urgent public health concerns. African American (AA) women have about twice the risk of preterm birth and low birthweight compared with non-Hispanic white women and are more likely to suffer from complications of pregnancy and severe maternal morbidity. As these disparities worsen, there has been renewed focus on perinatal care. The perinatal period, those weeks before and after birth, has important implications for a woman's health and that of her child. Unfortunately, the prevailing perinatal standard care model has been stagnant for decades and is not meeting the needs of AA women, especially with consideration to Social Determinants of Health (SDH) and the `fourth trimester' postpartum period proposed by the American College of Obstetricians and Gynecologists (ACOG). Patient navigation (PN) has demonstrated efficacy in improving consistency of care and addressing SDH among AA women. However, traditional PN models are economically challenging to scale and sustain, suggesting that a PN paradigm shift is needed ? one that minimizes the need for in-person navigators and places greater focus on clinic and systems level care improvement that integrates local and federally program support addressing SDH. Building on our decade of work in PN in women's health and care coordination checklists, we propose to develop a learning health care delivery approach to PN centered around an OPTIMIZE integrated and comprehensive perinatal care checklist. OPTIMIZE is highly aligned with ACOG endorsement of checklists for enhancing processes of care and teamwork. Through a Hybrid type 1 cluster randomized effectiveness-implementation trial, we will compare the effectiveness of the OPTIMIZE intervention relative to standard care in improving patient receipt of integrated and comprehensive perinatal care (prenatal content, postpartum content, and SDH content) tailored to a woman's individual needs, while evaluating intervention implementation. N=600 AA women in their 1st or 2nd trimester of pregnancy will be recruited from 20 clinics affiliated with two community health center networks that provide the majority of perinatal care for AA women in Chicago. Clinics will be randomized 1:1 to standard care (control) or standard care plus OPTIMIZE checklist with PN support (intervention) starting from the initial prenatal visit and through 12-weeks postpartum. The OPTIMIZE checklist will scale the reach of navigators by facilitating coordination and integration of efforts across perinatal care domains and integrating a SDH orientation to perinatal care. The checklist, tailored to the workflow within each clinic, will contain prenatal, postpartum, and SDH content for each patient. The primary outcome is patient receipt of perinatal care components in these 3 content areas collected by medical records review. Secondary outcomes include depressive symptoms, breastfeeding, vaccine (Tdap, influenza, HPV) and contraception uptake. The Consolidated Framework for Implementation Research will guide our mixed-methods approach to evaluate intervention implementation and identify implementation facilitators and barriers.